Fixed udev rule to automatically pair devices

My understanding is that the pairing should take place when an iPhone is connected and the USB Ethernet device within it is recognised and automatically associated with the ipheth driver module by the kernel. The following udev 'match' components should be sufficient to identify such an event:

SUBSYSTEM=="usb"
ATTRS{idVendor}=="05ac"
DRIVER=="ipheth"

This required the following changes to the previous rule (which did not work):
1) The SUBSYSTEM is "usb", not "net", as we want to do the pairing when the iPhone USB Ethernet interface is detected, not when the ipheth module loaded for that interface creates the actual system Ethernet interface device (which is very much a "net" device).
2) The USB Ethernet interface device can indeed be identified by its driver, which is ipheth, but the match requires the use of the standard udev DRIVER component, not the ID_USB_DRIVER environment variable (which doesn't appear to ever be set).
3) The vendor information is actually stored in the 'base' iPhone device, which is the parent of the USB Ethernet interface device within the iPhone. As a result, ATTRS should be used rather than ATTR.